There was a Google Code Jam problem this year precisely about detecting the difference between the fair shuffle and the "terribly, terribly wrong" shuffle: http

There was a Google Code Jam problem this year precisely about detecting the difference between the fair shuffle and the "terribly, terribly wrong" shuffle: https://code.google.com/codejam/contest/2984486/dashboard#s=p2 https://code.google.com/codejam/contest/2984486/dashboard#s=...